Fred runs at average speed of 12km per hour and flies at an average speed of 76km per hour. they traveled a total distance of 120 km in 2 hours how long did it take her to run and fly

Fred ran for 0.5 hours and flied for 1.5 hours.

Step-by-step explanation:

Distance covers while running = d

Time taken to cover d distance = x

Speed while running = 12 km/h

Distance covers while flying = D

Time taken to cover D distance = y

Speed while running = 76 km/h

Total distance = 120 km

Total time taken = 2 hours

Average speed :

Here ,120 km = d + D

120 km = d + D

..[1]

x + y = 2 hours..[2]

Solving both equation by substitution method:

Putting value of x from [2] in [1]:

x = 2 - y

x = 2 - y = 2 - 1.5 = 0.5

Fred ran for 0.5 hours and flied for 1.5 hours.

answer: y = -12x + 108

step-by-step explanation: do (y = m x+b) formula.